The overall goal of this study is to develop, adapt and evaluate an intergenerational prevention intervention, named ?Wa? Kan ye? zah (Little Holy One),? with Fort Peck Assiniboine and Sioux caregivers and their 3-to-5- year-old children. The intervention aims to: 1) reduce symptoms of historical trauma and everyday stress among parents/caregivers, 2) improve parenting, and 3) improve children?s emotional and behavioral developmental outcomes to reduce future risk for suicide and substance use. The scientific premise of this work is rooted in understanding that high rates of historical and current trauma in Native communities compromise caregivers? mental health and parenting, which in turn affect early childhood behavior problems and adverse events that increase children?s risk for suicide and substance use in adolescent and young adulthood. Without intervention, this intergenerational cycle may repeat. Wa? Kan ye? zah will combine adapted elements of: 1) Trauma-Focused Cognitive Behavioral Therapy, an evidence-based intervention proven effective to reduce stress, depression and trauma-related symptoms, 2) Family Spirit, an evidence-based parent training program to promote positive early child development in Native American communities, and 3) cultural components informed by tribal-specific risk and protective factors for suicide and substance abuse identified in community-based studies that led to this proposal. The intervention will consist of 12 weekly individual lessons taught to parents and children (ages 3 to 5) at the Poplar and Wolf Point Head Start facilities by indigenous community health workers, a delivery strategy selected to enhance participant engagement, local acceptability and sustainability. Intervention timing is focused at a critical developmental phase?when primary attachment is still to parents, but while children are transitioning to greater self-regulation and cooperation with teachers and peers in Head Start classrooms. This study will use a randomized control trial (RCT) with an embedded single-case experimental design (SCED) to determine the effectiveness of the intervention on mental health and behavioral outcomes among N=120 parent-child dyads, while empirically exploring the added benefit of specific cultural components on parent/caregiver outcomes. on mental health and behavioral outcomes among N=120 parent-child dyads, while exploring the added benefit of cultural components on parent outcomes. The study plan is situated within a well-established trust relationship with tribal communities, innovative formative research that led to this proposal, and an experienced, multi- disciplined study team led by an indigenous PI.